This work involved the co-substitution of the two bioactive ions of strontium and magnesium into the hydroxyapatite (HA) coating which was then electrochemically deposited on Ti-6Al-4V ELI dental alloy (Gr.23) before and after treatment by Micro Arc Oxidation (MAO). The deposited layers were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The adhesion strength of the coating layer was estimated by using pull-off adhesion test. The adhesion strength of Sr/Mg-HA on the Ti-6Al-4V ELI dental alloy after MAO treatment was 1.79 MPa, which was higher than that before MAO treatment (1.62 MPa). The corrosion behavior of the alloy in artificial saliva environment at temperature ranged 293-323K was assessed by means of electrochemical techniques and potentiodynamic polarization curves. The corrosion protection to the alloy at 293K was increased from 67.98% before treatment by MAO to 75.87% after treatment. The antimicrobial properties of the coated alloy were evaluated against different bacteria and oral fungi (Candida).
The research involved attempt to inhibit the corrosion of Al-Si-Cu alloy in 2.5x10-3 mol.dm-3 NaOH solution (pH=11.4) by addition of six different inhibitors with three concentrations (1x10-3, 1x10-2, and 0.1 mol.dm-3). These inhibitors include three organic materials (sodium acetate, sodium benzoate, and sodium oxalate) and three inorganic materials (sodium chromate, disodium phosphate, and sodium sulphate). The data that concerning polarization behaviour are calculates which include the corrosion potential (Ecorr) and current density (icorr), cathodic and anodic Tafel slopes (bc & ba), and polarization resistance (Rp). Protection efficiency (P%) and activation energy (Ea) values were calculated for inhibition by the six inhibitors. The
... Show MoreAbstract: The development of highly sensitive sensors has become an efficient field of research. In this work, an ArF Excimer laser of 193 nm with a maximum pulse energy of 275 mJ, 15 ns pulse duration and a repetition rate of 1 Hz is utilized to form a Laser Induced Periodic Surface Structures (LIPSS) of three different morphologies (nanochains, contours, grooves) on surface of CR39 polymer at a fluence range above the ablation threshold (250 mJ/cm2). The laser ablated polymer surface is then Surface Enhanced Raman Scattering (SERS) activated by deposition of a gold layer of 30 nm thickness. The capability of the produced substrate for surface enhanced Raman scattering is evaluated through thiophenol as an analyte molecule. It is observ
... Show MoreThis study aimed to evaluate the surface changes of commercial pure Titanium disks (CP Ti) and the Ti 13Nb 13 Zr (Alloy) with a zigzag pattern of laser surface treatment. In vitro, experimental study of CNC Laser treatment on the CP Ti and Alloy disks. Texturing the surfaces of CP Ti and Alloy disks via CNC laser, the sample disks were analyzed using surface roughness, wettability and FESEM. The FESEM revealed a proper increase in the surface texturing and roughness on macro and micro measures without crack formation or dramatic change of the core substance of the CP Ti and Alloy disks. The CNC laser is an effective and suitable method for surface texturing CP Ti and Alloy for dental implantology. Keywords: Commercial pure Titanium;
... Show MoreIn this work, an anti-reflection coating was prepared in the region (400-1000) nm of wavelength, with a double layer of silicon dioxide (SiO2) as an inner layer and the second layer of the mixture (SiO2) and titanium dioxide (TiO2) with certain ratios, as an outer layer using the chemical spraying method with a number of 6 sprays of layer SiO2 and 12 sprays of layer SiO2 - TiO2. Using the method of chemical spraying deposited on the glass as a substrate with a different number of sprays of SiO2, and a fixed number of TiO2-SiO2. The optical and structural properties were determined using UV-Vis spectroscopy and atomic force mi
... Show MoreThe driving idea for the present work was to combine the effect of polyvinyl alcohol (PVA) as corrosion inhibitor with the distance between the anodic and cathodic elements of the galvanic cell, beside their area ratio, in scope of synergistic suppression of galvanic corrosion on Cu/Fe model couple, using weight loss method. The performance affecting galvanic corrosion process has been tested for three major factors affect the process:
1. Four PVA inhibitor concentrations were selected to be (0, 1000, 4000 and 7000 ppm) in simulated cooling water.
2. Two cathode: anode area ratios as 1:1 and 2.4:1.
3. Two distances apart cathode – anode as 3 and 7 cm.
Maximum corrosion inhibition achieved was 86% which indicates that increa
An effort is made to study the effect of composite nanocoating using aluminum-9%wt silicon alloys reinforced with different percentage (0.5,1,2,4)wt.% of carbon nanotubes (CNTs) using plasma spraying. The effect of this composite on corrosion behavior for AA6061-T6 by extrapolation Tafel test in sea water 3.5wt% NaCl was invested. Many specimens where prepared from AA6061-T6 by the dimension (15x15x3)mm as this first set up and other steps include coating process, X-ray diffraction and SEM examination .The results show the CNTs increase the corrosion rate of the nanocomposite coatings with increasing the weight percentage of CNTs within the Al-Si matrix. Al-9wt%Si coating layer itself has less corrosion rate if compared with both n
... Show MoreThis study is concerned with the effect of adding two kinds of ceramic materials on the mechanical properties of (Al-7%Si- 0.3%Mg) alloy, which are zirconia with particle size (20μm > P.S ≥ 0.1μm) and alumina with particle size (20μm > P.S ≥ 0.1μm) and adding them to the alloy with weight ratios (0.2, 0.4, 0.6, 0.8 and 1%). Stirring casting method has been used to make composite material by using vortex technique which is used to pull the particles to inside the melted metals and distributed them homogenously.
After that solution treatment was done to the samples at (520ºC) and artificial ageing at (170ºC) in different times, it has been noticed that the values of hardness is increased with the aging time of the o
... Show MoreZinc oxide thin films were deposited by chemical spray pyrolysis onto glass substrates which are held at a temperature of 673 K. Some structural, electrical, optical and gas sensing properties of films were studied. The resistance of ZnO thin film exhibits a change of magnitude as the ambient gas is cycled from air to oxygen and nitrogen dioxide
Coating materials have an extraordinarily high use, for industrial or technical applications. This study compares the effect of short glass and polypropylene fibers on the hardness, water absorption and anti-bacterial activity of acrylic composites against Gram positive (Streptococcus sp.) and Gram negative bacteria (E.coli, Pseudomonas aeruginosa, Klebsiella sp.).To prepare acrylic polymer and acryliccomposites (glass fibers and polypropylene fiber) the weight fraction (20 %,) (v0= lama acrylic, v1= lama acrylic/ glass fiber, and v2= lama acrylic /poly propylene fiber), of chopped glass fibers and polypropylene were added to acrylic , the resultant solution was stirred by hand for 5 minutes, using the Hand-lay-up technique.
Results s